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1.
Sensors (Basel) ; 24(9)2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38732956

ABSTRACT

Virtual reality (VR) is used in many fields, including entertainment, education, training, and healthcare, because it allows users to experience challenging and dangerous situations that may be impossible in real life. Advances in head-mounted display technology have enhanced visual immersion, offering content that closely resembles reality. However, several factors can reduce VR immersion, particularly issues with the interactions in the virtual world, such as locomotion. Additionally, the development of locomotion technology is occurring at a moderate pace. Continuous research is being conducted using hardware such as treadmills, and motion tracking using depth cameras, but they are costly and space-intensive. This paper presents a walk-in-place (WIP) algorithm that uses Mocopi, a low-cost motion-capture device, to track user movements in real time. Additionally, its feasibility for VR applications was evaluated by comparing its performance with that of a treadmill using the absolute trajectory error metric and survey data collected from human participants. The proposed WIP algorithm with low-cost Mocopi exhibited performance similar to that of the high-cost treadmill, with significantly positive results for spatial awareness. This study is expected to contribute to solving the issue of spatial constraints when experiencing infinite virtual spaces.


Subject(s)
Algorithms , Virtual Reality , Walking , Humans , Walking/physiology , Male , Adult , Female , User-Computer Interface , Motion
2.
J Dermatol ; 51(5): 684-690, 2024 May.
Article in English | MEDLINE | ID: mdl-38321615

ABSTRACT

Dutasteride 0.5 mg is a dual inhibitor of 5α-reductase type I and II and was approved in Korea in 2009 for treating androgenetic alopecia (AGA) in men. We investigated the 5-year efficacy and safety of dutasteride 0.5 mg in Korean men with AGA using the basic and specific (BASP) classification. This retrospective analysis included 99 male AGA patients aged ≥18 years who were treated with dutasteride 0.5 mg for at least 5 years from October 2009 to December 2016 at Kyung Hee University Hospital in Gangdong. Patient photographs were scored using the BASP classification, and the Investigator Global Assessment (IGA) was performed using a seven-point scale. Patient improvement (IGA score ≥1) and prevention of disease progression (IGA score ≥0) were 89.9% (89/99) and 93.9% (93/99), respectively. According to the BASP classification, 52.5% (52/99) of the basic type, 75% (15/20) of the specific F type, and 82.2% (60/73) of the specific V type showed clinical improvement after 5 years of treatment. Dutasteride demonstrated long-term safety and efficacy in Korean male patients with AGA over a period of at least 5 years, with results comparable to those of other long-term efficacy studies of finasteride 1 mg in male patients with AGA.


Subject(s)
5-alpha Reductase Inhibitors , Alopecia , Dutasteride , Humans , Male , Alopecia/drug therapy , Dutasteride/adverse effects , Dutasteride/administration & dosage , Dutasteride/therapeutic use , Retrospective Studies , Adult , 5-alpha Reductase Inhibitors/adverse effects , 5-alpha Reductase Inhibitors/administration & dosage , 5-alpha Reductase Inhibitors/therapeutic use , Republic of Korea , Middle Aged , Treatment Outcome , Young Adult , Disease Progression , Time Factors , Aged
3.
Med Sci Monit ; 30: e942574, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38297827

ABSTRACT

BACKGROUND Ketamine, a compelling candidate for neuropathic pain management, has attracted interest for its potential to elevate brain-derived neurotrophic factor (BDNF) levels. We aimed to assess the effects of intrathecally administered ketamine on the cerebrospinal fluid (CSF) levels of BDNF(c-BDNF) and allodynia in a rat model of traumatic brain injury (TBI). MATERIAL AND METHODS Forty-five rats were divided into 3 groups: sham operation (Group S), untreated TBI (Group T), and ketamine-treated TBI (Group K), with 15 rats in each group. Rats were anesthetized, and their skulls were secured in a stereotactic frame before undergoing craniotomy. A controlled cortical impact (CCI) was induced, followed by injection of ketamine (3.41 µg/g) into the CSF in Group K. In Group T, no drug was injected after CCI delivery. On postoperative days (POD) 1, 7, and 14, the 50% mechanical withdrawal threshold (50% MWT) and c-BDNF levels were assessed. RESULTS Groups T and K exhibited a significantly lower 50% MWT than Group S on POD 1(6.6 [5.7, 8.7] g, 10.0 [6.8, 11.6] g, and 18.7 [11.6, 18.7] g, respectively; P<0.001). The c-BDNF levels in Group K were significantly higher than those in Groups S and T on POD 1 (18.9 [16.1, 23.0] pg/ml, 7.3 [6.0, 8.8] pg/ml, and 11.0 [10.6, 12.3] pg/ml, respectively; P=0.006). CONCLUSIONS Intrathecal ketamine administration did not exhibit anti-allodynic effects following mild TBI. c-BDNF level is a promising potential indicator for predicting the expression of allodynia after mild TBI.


Subject(s)
Brain Concussion , Ketamine , Rats , Animals , Hyperalgesia/drug therapy , Ketamine/pharmacology , Ketamine/therapeutic use , Brain-Derived Neurotrophic Factor/metabolism , Rats, Sprague-Dawley
4.
J Dermatol ; 51(4): 532-538, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38366757

ABSTRACT

Primary cutaneous malignancies are among the most commonly diagnosed types of cancer worldwide. We aimed to examine the incidence and 5-year survival rates of all types of primary cutaneous malignancies in the Korean population. Data from the Korean Nationwide Cancer Registry from 1999 to 2019 were analyzed. The crude incidence rates, age-standardized incidence rates, and 5-year relative survival rates of each type of skin cancer were calculated. A total of 89 965 patients were diagnosed with primary cutaneous malignancies, which was a 7-fold increase from 1999 to 2019. The age-standardized incidence rates increased 3.4-fold in basal cell carcinoma (3.7/100 000 person-years), 2.0-fold in squamous cell carcinoma (1.6/100 000 person-years), 12.0-fold in Bowen disease (1.2/100 000 person-years), and 1.8-fold in malignant melanoma (0.7/10 000 person-years) in 2019. Average annual percentage changes in age-standardized incidence rates were statistically significant in basal cell carcinoma (15.8%), Bowen disease (5.8%), squamous cell carcinoma (5.1%), malignant melanoma (1.2%), melanoma in situ (1.1%), dermatofibrosarcoma protuberans (1.2%), mycosis fungoides (0.5%), primary cutaneous CD30+ T-cell proliferations (0.5%), adnexal and skin appendage carcinoma (0.4%), extramammary Paget's disease (0.2%), and Merkel cell carcinoma (0.2%). The 5-year relative survival rates were the highest in basal cell carcinoma (103.3%), followed by dermatofibrosarcoma protuberans (99.7%) and mycosis fungoides (96.6%), and lowest in angiosarcoma (24.7%). The 5-year relative survival rates steadily increased in extramammary Paget's disease (23.6%), cutaneous B-cell lymphoma (21.3%), mycosis fungoides (20.2%), extranodal NK/T-cell lymphoma, nasal type (18.1%), and malignant melanoma (16.1%) from 1996-2000 to 2015-2019. Most primary cutaneous malignancies have increased in incidence and survival rates in the Korean population, but to varying extents depending on the type of skin cancer.


Subject(s)
Bowen's Disease , Carcinoma, Basal Cell , Carcinoma, Squamous Cell , Dermatofibrosarcoma , Melanoma , Mycosis Fungoides , Paget Disease, Extramammary , Skin Neoplasms , Humans , Child, Preschool , Melanoma/epidemiology , Incidence , Survival Rate , Skin Neoplasms/diagnosis , Carcinoma, Basal Cell/epidemiology , Mycosis Fungoides/diagnosis , Carcinoma, Squamous Cell/epidemiology , Republic of Korea/epidemiology
6.
J Dermatol ; 50(10): 1335-1338, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37208851

ABSTRACT

Alopecia totalis (AT) and alopecia universalis (AU) is known to have a poor prognosis with high relapse rate, and treatment failure is observed in most patients, regardless of the type of therapy. Although treatment and the prognosis of AT and AU have improved in recent years, old data are routinely cited in recent review papers without questioning them. The authors aimed to study the clinical characteristics and prognosis of AT and AU to update and compare the results with those of previously reported studies. The authors retrospectively reviewed patients diagnosed with AT and AU from 2006 to 2017 in a single institution. Of the 419 patients, the mean age at first episode was 22.9 years, and 24.6% had early onset (≤13 years). During follow-up, 53.9% had more than 50% hair growth, and 19.6% of patients showed >90% hair growth. Among patients who showed >50% improvement, 36.7% had no recurrence. In early studies conducted in the 1950s and 1960s, the chance of full hair regrowth was reported to be <10%. In our study, patients with >90% improvement in AT and AU accounted for 19.6% of patients. The authors provide an update on data regarding the prognoses of AT and AU.


Subject(s)
Alopecia Areata , Humans , Retrospective Studies , Alopecia Areata/drug therapy , Alopecia/therapy , Alopecia/drug therapy , Prognosis , Hair
7.
J Cosmet Dermatol ; 22(8): 2239-2245, 2023 Aug.
Article in English | MEDLINE | ID: mdl-36943760

ABSTRACT

BACKGROUND: Extracellular matrix (ECM) components promote the development of skin wounds by providing biological scaffolds and regenerative microenvironments. AIMS: To evaluate the beneficial effects of human dermal fibroblast-derived ECM after fractional carbon dioxide laser resurfacing in Asians. PATIENTS/METHODS: In this double-blind, randomized, vehicle-controlled, split-face study, 15 participants with features of facial skin aging were treated with a single session of fractional carbon dioxide laser, followed by the application of either ECM (ECM group) or placebo (control group). In vivo skin parameters were measured at baseline and after 4 and 12 weeks of treatment using the Antera 3D®, Cutometer® MPA580, Dermascan®, and Tewameter®. RESULTS: A total of 14 participants (mean age 45.1 ± 9.7 years) completed the study. The change in melanin level was significantly lower in the ECM group than in the control group at week 12 (p < 0.05). Transient increase in erythema level was observed at week 4 in the control group, and the change in the erythema level was greater in the control group than in the ECM group (p = 0.014). Though the ECM group showed improvements in the dermal density, texture, transepidermal water loss, marionette lines (volume, maximum depth, and average depth), and nasolabial folds (volume, maximum depth, and length), no significant differences were found between the two groups. Treatment-related adverse events were not reported. CONCLUSIONS: We suggest that human dermal fibroblast-derived ECM may be used as adjunctive therapy after fractional carbon dioxide resurfacing to prevent postinflammatory hyperpigmentation in Asians.


Subject(s)
Extracellular Matrix , Hyperpigmentation , Laser Therapy , Lasers, Gas , Skin Aging , Adult , Humans , Middle Aged , Asian , Carbon Dioxide , Cicatrix/etiology , Erythema/etiology , Erythema/prevention & control , Hyperpigmentation/etiology , Hyperpigmentation/prevention & control , Laser Therapy/adverse effects , Lasers, Gas/adverse effects , Treatment Outcome , Double-Blind Method
8.
Phys Rev Lett ; 129(22): 221603, 2022 Nov 23.
Article in English | MEDLINE | ID: mdl-36493439

ABSTRACT

We investigate the standard and dual Bondi-Metzner-Sachs (BMS) supertranslation generators on a black hole horizon and draw some conclusions about black hole physics. Recently, it has been shown that in addition to conventional BMS supertranslation symmetries, there exists an additional infinite set of magnetic asymptotic symmetries, dual BMS supertranslations, again parametrized by a function on the two-sphere. We show that the Dirac bracket between these generators exhibits an anomalous central term when one parameter function exhibits a singularity in the complex stereographical coordinates on the sphere. In order to preserve general coordinate invariance, we demonstrate that this central term can be removed by postulating a holographic gravitational Chern-Simons theory on the horizon. This indicates that for an anomaly-free theory of quantum gravity in the presence of a black hole, one should include a boundary theory on the horizon.


Subject(s)
Physics
9.
Expert Syst Appl ; 206: 117811, 2022 Nov 15.
Article in English | MEDLINE | ID: mdl-35712056

ABSTRACT

Coughing is a typical symptom of COVID-19. To detect and localize coughing sounds remotely, a convolutional neural network (CNN) based deep learning model was developed in this work and integrated with a sound camera for the visualization of the cough sounds. The cough detection model is a binary classifier of which the input is a two second acoustic feature and the output is one of two inferences (Cough or Others). Data augmentation was performed on the collected audio files to alleviate class imbalance and reflect various background noises in practical environments. For effective featuring of the cough sound, conventional features such as spectrograms, mel-scaled spectrograms, and mel-frequency cepstral coefficients (MFCC) were reinforced by utilizing their velocity (V) and acceleration (A) maps in this work. VGGNet, GoogLeNet, and ResNet were simplified to binary classifiers, and were named V-net, G-net, and R-net, respectively. To find the best combination of features and networks, training was performed for a total of 39 cases and the performance was confirmed using the test F1 score. Finally, a test F1 score of 91.9% (test accuracy of 97.2%) was achieved from G-net with the MFCC-V-A feature (named Spectroflow), an acoustic feature effective for use in cough detection. The trained cough detection model was integrated with a sound camera (i.e., one that visualizes sound sources using a beamforming microphone array). In a pilot test, the cough detection camera detected coughing sounds with an F1 score of 90.0% (accuracy of 96.0%), and the cough location in the camera image was tracked in real time.

10.
Waste Manag Res ; 39(1): 165-173, 2021 Jan.
Article in English | MEDLINE | ID: mdl-32951533

ABSTRACT

Kitchen waste (KW) has gradually become a prominent problem in municipal solid waste treatment. Hydrothermal liquefaction (HTL) is a promising method used to make fuel oil from food and KW. However, the upgrading of bio-oil is particularly important for the sake of industrial reuse. In this study, the KW from university restaurants was subjected to HTL experiments in order to study theoretical feasibility. With the change of conversion temperature and residence time, the optimal conversion working conditions in this study were determined according to the quality and yield of the bio-oil. Moreover, the bio-oil upgrading effects of different additives (hydrogen chloride, sodium hydroxide, and iron(III) chloride) on the HTL of KW were studied. Alkaline additives have an inhibitory effect on the bio-oil yield and positive effect on coke yield. Acidic additives and iron (Fe)-containing additives can promote bio-oil yield. As an important aspect of upgrading, the effect on the nitrogen content of bio-oil with additives was revealed. The alkaline and Fe-containing additives have little effect on reducing the viscosity of the bio-oil while with the appropriate ratio (2.5 mol•kg-1) of acidic additives to the raw material, the static and dynamic fluidity of the oil phase products are reduced to about 0.1 Pa•s.


Subject(s)
Biofuels , Ferric Compounds , Biomass , Humans , Plant Oils , Polyphenols , Temperature , Water
11.
Mol Cells ; 43(11): 899-908, 2020 Nov 30.
Article in English | MEDLINE | ID: mdl-33243935

ABSTRACT

Intrinsically disordered proteins or regions (IDPs or IDRs) are widespread in the eukaryotic proteome. Although lacking stable three-dimensional structures in the free forms, IDRs perform critical functions in various cellular processes. Accordingly, mutations and altered expression of IDRs are associated with many pathological conditions. Hence, it is of great importance to understand at the molecular level how IDRs interact with their binding partners. In particular, discovering the unique interaction features of IDRs originating from their dynamic nature may reveal uncharted regulatory mechanisms of specific biological processes. Here we discuss the mechanisms of the macromolecular interactions mediated by IDRs and present the relevant cellular processes including transcription, cell cycle progression, signaling, and nucleocytoplasmic transport. Of special interest is the multivalent binding nature of IDRs driving assembly of multicomponent macromolecular complexes. Integrating the previous theoretical and experimental investigations, we suggest that such IDR-driven multiprotein complexes can function as versatile allosteric switches to process diverse cellular signals. Finally, we discuss the future challenges and potential medical applications of the IDR research.


Subject(s)
Intrinsically Disordered Proteins/metabolism , Macromolecular Substances/metabolism , Humans , Signal Transduction
12.
Article in English | MEDLINE | ID: mdl-27775535

ABSTRACT

When a gene shows varying levels of expression among normal people but similar levels in disease patients or shows similar levels of expression among normal people but different levels in disease patients, we can assume that the gene is associated with the disease. By utilizing this gene expression heterogeneity, we can obtain additional information that abets discovery of disease-associated genes. In this study, we used collaborative filtering to calculate the degree of gene expression heterogeneity between classes and then scored the genes on the basis of the degree of gene expression heterogeneity to find "differentially predicted" genes. Through the proposed method, we discovered more prostate cancer-associated genes than 10 comparable methods. The genes prioritized by the proposed method are potentially significant to biological processes of a disease and can provide insight into them.


Subject(s)
Computational Biology/methods , Gene Expression Profiling/methods , Genetic Association Studies/methods , Prostatic Neoplasms/genetics , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Databases, Genetic , Humans , Male , Prostatic Neoplasms/metabolism
13.
J Environ Manage ; 196: 710-718, 2017 Jul 01.
Article in English | MEDLINE | ID: mdl-28371748

ABSTRACT

Greenhouse gas (GHG) emission factors previously reported from various waste incineration plants have shown significant variations according to country-specific, plant-specific, and operational conditions. The purpose of this study is to estimate GHG emissions and emission factors at nine incineration facilities in Korea by measuring the GHG concentrations in the flue gas samples. The selected incineration plants had different operation systems (i.e., stoker, fluidized bed, moving grate, rotary kiln, and kiln & stoker), and different nitrogen oxide (NOx) removal systems (i.e., selective catalytic reduction (SCR) and selective non-catalytic reduction (SNCR)) to treat municipal solid waste (MSW), commercial solid waste (CSW), and specified waste (SW). The total mean emission factors for A and B facilities for MSW incineration were found to be 134 ± 17 kg CO2 ton-1, 88 ± 36 g CH4 ton-1, and 69 ± 16 g N2O ton-1, while those for CSW incineration were 22.56 g CH4 ton-1 and 259.76 g N2O ton-1, and for SW incineration emission factors were 2959 kg CO2 ton-1, 43.44 g CH4 ton-1 and 401.21 g N2O ton-1, respectively. Total emissions calculated using annual incineration for MSW were 3587 ton CO2-eq yr-1 for A facility and 11,082 ton CO2-eq yr-1 for B facility, while those of IPCC default values were 13,167 ton CO2-eq yr-1 for A facility and 32,916 ton CO2-eq yr-1, indicating that the emissions of IPCC default values were estimated higher than those of the plant-specific emission factors. The emission of CSW for C facility was 1403 ton CO2-eq yr-1, while those of SW for D to I facilities was 28,830 ton CO2-eq yr-1. The sensitivity analysis using a Monte Carlo simulation for GHG emission factors in MSW showed that the GHG concentrations have a greater impact than the incineration amount and flow rate of flue gas. For MSW incineration plants using the same stoker type in operation, the estimated emissions and emission factors of CH4 showed the opposite trend with those of NO2 when the NOx removal system was used, whereas there was no difference in CO2 emissions.


Subject(s)
Greenhouse Effect , Incineration , Refuse Disposal , Gases , Republic of Korea , Solid Waste
14.
Clin Ther ; 32(6): 1178-87, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20637970

ABSTRACT

BACKGROUND: Avanafil is a selective phosphodiesterase type 5 inhibitor being developed for the treatment of erectile dysfunction. OBJECTIVE: This study was conducted to meet Korean regulatory requirements for the marketing of avanafil. To this end, tolerability and pharmacokinetic properties of single and multiple oral doses of avanafil in healthy Korean male volunteers were assessed. METHODS: A double-blind, randomized, placebo-controlled, parallel-group, dose-escalation study was conducted at the Asan Medical Center (Seoul, Korea). Subjects were randomized to receive either drug or placebo in blocks according to each dose. Subjects were randomly allocated to receive 50-, 100-, or 200-mg tablets of avanafil or placebo once daily for 7 days (avanafil:placebo, 8:2 in each dose group). Tolerability was assessed by monitoring vital signs and results of laboratory tests, 12-lead ECGs, and color discrimination tests. Blood samples of approximately 6 mL were collected in heparinized tubes before and 0.1, 0.33, 0.5, 0.75, 1, 1.5, 2, 3, 4, 6, 8, 12, and 24 hours after drug administration on days 1 and 7. Plasma concentrations of avanafil were measured using LC-MS/MS. Pharmacokinetic parameters of avanafil on days 1 and 7 were determined by noncompartmental analysis and compared among the 3 dose groups. RESULTS: Of the 32 healthy male subjects initially enrolled, 30 completed the study. The mean (SD) age, height, and weight of the participants were 23.4 (1.7) years, 175.0 (5.4) cm, and 70.3 (8.9) kg, respectively. Adverse events were reported by 20 of 25 subjects (80%) taking avanafil and by 4 of 6 (67%) taking placebo. No serious adverse events were reported, and there were no clinically relevant changes in vital signs, ECG recordings, physical examination findings, or color discrimination test results. All the adverse events resolved spontaneously. Avanafil reached a mean T(max) at 0.33 to 0.52 hour after dosing and then declined, with a mean apparent t1/2 of 5.36 to 10.66 hours. AUC and C(max) were proportional to dose, and the mean accumulation index on day 7 after a single daily dose of avanafil was 0.98. CONCLUSION: Avanafil was generally well tolerated and had linear pharmacokinetic properties at daily doses of 50 to 200 mg over 7 days in these healthy Korean male volunteers. Korean National Study Registration Number: 3466.


Subject(s)
Phosphodiesterase 5 Inhibitors , Pyrimidines/pharmacokinetics , Adult , Area Under Curve , Dose-Response Relationship, Drug , Double-Blind Method , Half-Life , Humans , Male , Pyrimidines/administration & dosage , Pyrimidines/adverse effects
15.
Waste Manag ; 27(5): 604-13, 2007.
Article in English | MEDLINE | ID: mdl-17258445

ABSTRACT

Operation parameters such as waste feed rate, air supply, and temperature of the gas in incineration plants should be carefully determined for various situations, which include seasonal and annual changes in fuel characteristics, and performance change of the hardware. These changes may cause off-design point operation of the incinerators, which results in many problems in operation of the flue gas treatment system, low-oxygen in the combustion chamber, thermal damage of the incinerator wall, and so on. In this study, an engineering approach using computational tools along with field tests and observation is presented. For computational tools, a 0-dimensional model for heat and mass balance, computational fluid dynamics (CFD), and a global prediction model for dioxin are employed. They play a key role in diagnosing incineration systems and evaluating changes in operating conditions. The typical results of each tool are reported, and examples of improvement in operating performance are described.


Subject(s)
Engineering/instrumentation , Incineration , Models, Theoretical , Refuse Disposal/methods , Air Movements , Dioxins/analysis , Dioxins/chemistry , Engineering/methods , Environmental Monitoring , Facility Design and Construction , Gases , Hazardous Waste/analysis , Seasons , Temperature
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